How Impressive Was Samsung's Galaxy S4 Launch?

No smartphone maker has challenged Apple like Samsung does. The South Korean conglomerate's Galaxy S lineup has proven to be the most viable contender for the title of "iPhone killer," a moniker that countless rivals have pursued to no avail.

In January, Samsung announced that its flagship product family had reached a cumulative total of 100 million units in channel sales over the first three generations. The newest addition is the Galaxy S4, which was unveiled in March and launched near the tail end of April.

An unnamed exec told The Chosun Ilbo that the company had "supplied" 4 million units to carriers worldwide by the end of April. As of last Friday, Samsung had shipped more than 6 million, and the company expects to break 10 million units by month's end.

That's an impressive headline figure, as 4 million units is pretty close to the 5 million iPhone 5 units that Apple sold during its last launch weekend. However, the devil is in the details. Since most of Samsung's sales are channel sales, a chunk of those 4 million units were making their way through the company's expansive distribution network at the end of April. There's a considerable difference between Samsung's estimated sell-through figures compared to its sell-in digits. The Galaxy S4 now qualifies as Samsung's fastest-selling smartphone, which is impressive considering the lukewarm reception it got after being unveiled.

Last year, the predecessor Galaxy S III dethroned the iPhone 4S as the top-selling smartphone model in the world, only for the iPhone 5 to reclaim that title later in the year. With Apple currently in a mid-cycle lull ahead of new iPhones this fall, the Galaxy S4 could easily become the top seller for a quarter or two, before Apple puts the heat on later.

Also, don't forget that the GS4 saw some inventory challenges in the U.S, which delayed its launch on Sprint and T-Mobile. Sprint began to get stock before April ended, but T-Mobile had to push launch into May. AT&T was the first to get the device, with retail availability on April 27, while Verizon Wireless is the last of the big four to get the GS4, which is slated for later this month.

That means that most of the U.S. launch wasn't captured in the 4 million units that Samsung announced. Even though many of its features are somewhat gimmicky, the Galaxy S4 is off to a strong start.

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